Robot hand

ABSTRACT

The invention provides a robot hand that can mimic the movements of a human hand in operation. The robot hand includes a thumb and at least one opposing finger having at least two phalanxes connectable to each other by a distal phalanx joint. The thumb of the robot hand also includes a joint which allows the thumb to move transversely with respect to the opposing fingers. The robot hand can also include one or more additional fingers disposed on an opposite side of the thumb. The robot hand can be operated mechanically or electrically through controlling motors.

The U.S. Government has a nonexclusive, nontransferable, irrevocablepaid-up license to practice or have practiced this invention for or onits behalf as provided for by the terms of Grant Number DAMD17-94-J-4502awarded by the U.S. Department of the Army.

FIELD OF THE INVENTION

The invention is directed to a controllable remote grasping device, moreparticularly, a robot hand, which can be used in a remote manipulator,such as a surgical manipulator as described in U.S. patent application,Ser. No. 08/206,450, filed Mar. 4, 1994, now issued as U.S. Pat. No.5,599,151, which is hereby incorporated by reference, and the like use.

BACKGROUND OF THE INVENTION

Manipulable hand apparatuses have been disclosed and are available inmany industries, e.g. the medical device industry. The followingreferences disclose examples of different types of manipulable handapparatuses or handling devices used in the medical or other industries:U.S. Pat. No. 4,315,650 issued to Yoshida; U.S. Pat. No. 4,575,297issued to Richter; U.S. Pat. No. 2,733,545 issued to Guadagna; U.S. Pat.No. 422,373 issued to Caldwell; U.S. Pat. No. 2,765,930 issued to Greeret al.; U.S. Pat. No. 3,212,651 issued to Specht et al; and EuropeanPatent Application Publication No. 0 640 319 A1 to Ortiz. In thesereferences, different mechanical structures are utilized to controlmovements of a hand-type clamping device which is remotely controlled bya master control such as a human's hand, etc. However, most of theseconventional clamping devices are complicated in structure. In addition,the conventional devices do not permit performance as a virtual hand ata remote site under master control. As a result, the conventionaldevices do not provide for a surgeon to perform surgery through avirtual reality modality. Further, even if the conventional devices aresubstantially altered to function as a virtual hand by adding numerousother pieces, the devices are too expensive to make and not practical inuse.

Therefore, a substantial need exists for a robot hand which provides foran easy mechanism and is capable of performing surgery by transmissionof the movement of a surgeon's hand.

SUMMARY OF THE INVENTION

The invention is directed to a controllable remote grasping device, moreparticularly, a robot hand, which can be used as a remote manipulator,such as a surgical manipulator, and the like use.

In one embodiment generally in accordance with the principles of thepresent invention, a robot hand comprises a thumb including at least twophalanxes connectable to each other by a first thumb joint and having asecond thumb joint which allows the thumb to move transversely withrespect to the phalanxes; at least two fingers, disposed on an oppositeside of the thumb, each including at least two phalanxes connectable toeach other by a first finger joint; the thumb being movable such as tooppose a selected one of at least two fingers and is able toindividually grip between the selected finger and the thumb.

In some embodiments, at least one cable is connected to at least one ofthe phalanxes of each of the fingers and the thumb to move the phalanxesof each of the fingers and the thumb relative to each other. The cablecan be operated from the proximal aspect of the robot hand by acontroller.

The phalanxes of the robot hand are rotatable relative to one another toselectively cause the phalanxes to assume a bent or linear position bypushing or pulling on the cable. The phalanxes can be spring-biased tomove from the bent position into a straight position by a spiral spring.The cable can pass through the spiral spring. In an alternativeembodiment, the phalanxes are spring-biased to move from the bentposition into a straight position by a flat spring. When all the fingersand thumb are in a substantially linear position, a robot hand of asuitable size can be passed through a medical trocar or the like. Thisadvantageously provides for a robot hand of the invention to be usedduring minimally invasive surgical procedures, for example, alaparoscopic procedure.

A disposable glove can be applied over the robot hand to cover the thumband the fingers for uses such as during endoscopic surgery. The glove isremoved and renewed after a surgical operation.

In some embodiments, the robot hand can be operated remotely by acontrolling system and the robot hand can be disconnected and removedfrom the controlling system for sterilization, maintenance, etc.

The remote grasping device can also comprise: a hand base; a first digitmember, the first digit member including: a first distal phalanx, afirst middle phalanx, and a first base phalanx, wherein the first basephalanx is pivotally attached to the hand base and constructed andarranged to provide for the first distal phalanx and the first middlephalanx to rotate as a single unit in at least two planes. A seconddigit member is arranged opposite of the first digit member, the seconddigit member including: a second distal phalanx, a second middlephalanx, and a second base phalanx, wherein the second base phalanx ispivotally attached to the hand base and constructed and arranged toprovide for the second distal phalanx and the second middle phalanx torotate as a single unit in at least two planes.

The movements of the first and second digit members can be mechanicallyor electrically controlled. In one embodiment, the movements of thefirst and second digit members can be controlled by a data glove.

In a further embodiment of the remote grasping device, the first distalphalanx can have a proximal end; the first middle phalanx can have aproximal end and a distal end and the first base phalanx can have adistal end. The proximal end of the first distal phalanx is pivotablyattached to the distal end of the first middle phalanx for rotationaround a first distal axis, and the proximal end of the first middlephalanx is pivotably attached to the distal end of the first basephalanx for rotation around a first middle axis. The first proximal axisand the first middle axis are substantially parallel provided that thefirst middle phalanx is generally linear. In addition, the second distalphalanx can have a proximal end and the second middle phalanx can have aproximal end and a distal end. The second base phalanx can have a distalend. The proximal end of the second distal phalanx is pivotably attachedto the distal end of the second middle phalanx for rotation around asecond distal axis, and the proximal end of the second middle phalanx ispivotably attached to the distal end of the second base phalanx forrotation around a second middle axis. The second proximal axis and thesecond distal axis are substantially parallel provided that the firstmiddle phalanx is generally linear.

One advantage of the present invention is that it provides an easymechanism for a robot hand. Another advantage of the invention is thatit allows the use of right and left robot hands together at a surgicalsite which can work collectively like a human surgeon's hands. Such asystem would provide for a surgeon to perform surgery through a virtualreality modality. Such a system would also permit skilled or specializedsurgeons from one location to perform surgery at another location bytransmission of surgeon's right and left hand movements to the right andleft hand movements of robot's hands.

These and other advantages and features, which characterize theinvention are pointed out with particularity in the claims annexedhereto and forming a part hereof. However, for a better understanding ofthe invention and the advantages and objectives obtained by its use,reference should be made to the drawings which form a further parthereof and to the accompanying descriptive matter, in which there isdescribed a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of one embodiment of a robot hand generallyaccording to the present invention.

FIG. 2 is a schematic view of one embodiment of a glove for the robothand.

FIG. 3A is a longitudinal, cross-sectional view of a finger of the handwhen a portion of the finger is pulled such that the finger is in a bentposition.

FIG. 3B is a longitudinal, cross-sectional view of a finger of the handwhen the finger is released such that the finger is in a straightposition.

FIG. 4A is a plane top view of another embodiment of a robot hand.

FIG. 4B is an elevational side view of the embodiment of the robot handof FIG. 4A.

FIG. 5 is a schematic view of a control system in connection with arobot hand.

FIG. 6 is a transverse, cross-sectional view of a pulley cable.

FIG. 7 is a transverse, cross-sectional view of another embodiment of apulley cable.

FIG. 8 is a block diagram of a control system of the robot hand.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the figures, wherein like numbers refer to like partsthroughout the several views, FIG. 1 shows a robot hand 1 generallyconsistent with the principles of the present invention. The robot hand1 is constructed to mimic movements of a human hand. The robot hand 1can be operated mechanically by a remote human hand. Alternatively, therobot hand 1 can be operated electrically, receiving input instructionsfrom a data glove or a computer, as generally shown in FIG. 5.

In FIG. 1, the illustrated robot hand 1 is similar to a human hand inthat it has a thumb 2, a first finger 3, a second finger 4, and a handbase 5. The robot hand 1 can be covered by a glove 6 as shown in FIG. 2.As shown in FIG. 1, the thumb 2 includes a base phalanx 7, a middlephalanx 8, and an end phalanx 9. The fingers 3,4 include a base phalanx7′,7″, a middle phalanx 8′,8″, and an end phalanx 9′,9″, respectively.Each end phalanx 9,9′,9″ is disposed at a distal end 100, 100′, 100″ ofthe thumb 2 or fingers 3,4. Each end phalanx 9,9′,9″ has a proximal end102,102′,102″. Each middle phalanx 8,8′, 8″ has a proximal end104,104′104″ and a distal end 106,106′,106″. Each base phalanx 7,7′,7″has a distal end 108,108′,108″. The proximal end 102,102′,102″ of theend phalanx 9,9′,9″ is pivotably attached or coupled to the distal end106,106′,106″ of the middle phalanx 8,8′,8″ for rotation around a distalaxis 110,110′,110″. The proximal end 104,104′,104″ of the base phalanx7,7″,7″ is pivotably attached or coupled to the distal end 108,108′,108″of the base phalanx 7, 7′, 7″for rotation around a proximal axis112,112′,112″. The distal axis and the proximal axis are substantiallyparallel when the middle phalanx 108, 108′, 108″ is substantiallylinear. Each phalanx is connected to the next phalanx by a joint 10. Asshown in FIG. 1, the end phalanx 9,9′,9″ is coupled to the distalphalanx 8,8′,8″ by a middle phalanx joint 115, 115′, 115″; and themiddle phalanx 8,8′,8″ is coupled to the base phalanx 7,7′,7″ by aproximal phalanx joint 116, 116′, 116″. The joint 10 can be any type ofsuitable connectors, including a coupled hinge, as shown.

FIG. 2 shows the robot hand 1 covered by glove 6, which is made out ofan elastic material, such as silicone, latex or any other suitablerubber or elastic material. The glove 6 can serve to protect themechanics of the robot hand 1. The glove 6 also can provide for repeatedsterile use of robot hand 1 and reduce the cleaning necessary after use.In addition, glove 6 can make it easier for the gloved robot hand tomove along a lumen or other medical guide, such as a trocar, forinsertion of the device into a body. The glove further helps reduce thepossibilities of pinching of structures along the path that the robothand passes. Furthermore, the glove 6 can be disposable after anoperation using the robot hand 1, e.g. an endoscopic surgical procedure.It will be appreciated that the robot hand 1 can comprise additionalfingers, for example, fingers 4, 5 etc., similar to the fingers 3, 4. Itwill also be appreciated that the hand glove 6 can be made correspondingto the modified robot hand, e.g. with additional fingers, withoutdeparting from the scope and spirit of the present invention.

In FIGS. 3A and 3B, a longitudinal cross-sectional view of the firstfinger 3 is shown. The cross-sectional views of FIGS. 3A and 3B couldalso be representative of finger 4 or thumb 2. As illustrated, middlephalanx joint 115′ connects the end phalanx 9′ to the middle phalanx 8′so that the end and middle phalanxes 9′ and 8′ are relatively rotatablearound the distal axis 110′. Proximal phalanx joint 116′ connects themiddle phalanx 8′ to the base phalanx 7′ so that the middle and basephalanxes 7′ and 8′ are relatively rotatable around the proximal axis112'.

The positioning of the phalanxes can be operated by a pulley mechanismutilizing cables. As used herein, a “cable” includes single or multiplestranded wire, plastic, or otherwise suitable material for operating arobot hand as disclosed herein. In the illustrated embodiment, cable 13′extends in a bore 50′ of the end phalanx 9′, a bore 51′ of the middlephalanx 8′, and a bore 52′ of the base phalanx 7′. The distal end of thecable 13′ is connected to the end phalanx 9′ at location 14′ distal tothe proximal end 102′ of the end phalanx 9′. The cable 13′ can befastened by a compression screw inserted via hole 15′ or other meanssuch as welding, gluing, etc. A spring 17′ is disposed around a portionof the cable 13′ proximate the middle phalanx joint 115′ between the endphalanx 9′ and the middle phalanx 8′. The two ends, 17 a′ and 17 b′, ofthe spring 17′ are retained in notches 124′, 126′ of the end phalanx 9′and the middle phalanx 8′, respectively. The spring 17′, biased againstand between the walls of the two notches 124′, 126′, can be a spiralspring, a flat spring or equivalent structure. The cable 13′ is operatedto rotate the end phalanx 9′, and the middle phalanx 8′, relative to oneanother, which mimics movements of a finger or thumb between the end andmiddle phalanxes. Accordingly, when the cable 13′ is pulled in adirection of the hand base 5 (FIG. 1), the end phalanx 9′ rotates aroundthe middle phalanx 8′ around the distal axis 110′ as shown in FIG. 3A.When the force to cable 13′ is released, the spring 17′ biases back theend phalanx 9′ from the middle phalanx 8′ around the distal axis 110′ soas to straighten the finger 3 as shown in FIG. 3B.

Another pulley or cable 12′ extends in a bore 120′ of the middle phalanx8 and a bore 122′ of the base phalanx 7′. The distal end of the cable12′ is connected to the middle phalanx 8′ at location 128′ distal to theproximal end 104′ of the middle phalanx 8′. This connection can be doneby fastening using a screw inserted via hole 130′ or other means such aswelding, gluing, etc. A spring 132′ is disposed around a portion of thecable 12′ proximate the proximal phalanx joint 116′ between the middlephalanx 8′ and the base phalanx 7′. The two ends, 132 a′ and 132 b′, ofthe spring 132′ are retained in notches 134′, 136′ of the middle phalanx8′ and the base phalanx 7′, respectively. The spring 132′, biasedagainst and between the walls of the two notches 134′, 136′, can be aspiral spring, a flat spring or equivalent structure. The cable 12′ isoperated to rotate the middle phalanx 8′ around the base phalanx 7′,which mimics movements of a digit (finger or thumb) between the middleand base phalanxes. Accordingly, when the cable 12′ is pulled in adirection of the hand base 5′, the middle phalanx 8′ moves relative tothe base phalanx 7′ as shown in FIG. 3A. When the force to cable 12′ isreleased, the spring 132′ biases back the middle phalanx 8′ from thebase phalanx 7′ so as to straighten the finger 3 as shown in FIG. 3B.

Finger 4 and thumb 2 have a similar longitudinal cross-sectional view asshown in FIGS. 3A and 3B. As a result, the two cables (12′, 13′) of eachof the fingers 3 and 4 move the middle phalanxes 8′,8″ against the basephalanxes 7′,7″ and move the end phalanxes 9′,9″ against the middlephalanxes 8′,8″.

As shown in FIG. 1, the fingers 3 and 4 are generally disposed to opposethe thumb 2 such that the movements between the thumb 2 and each of thefingers 3 and 4 allow gripping therebetween. That is, like a human hand,a robot hand according to the invention has an opposable thumb.

Further in FIG. 1, a spring 18 is connected between the base phalanx 7″of finger 4 and hand base 5. The spring 18 is used to move back (adduct)finger 4 with respect to the finger 3. Another spring (not visible) isconnected between the base phalanx 7′ of finger 3 and the hand base 5.This spring is positioned such that it can move back (adduct) finger 3with respect to finger 4. Thus, these springs assist in moving thefingers together. A pulley or cable (not visible) runs through spring18. When pulled towards hand base 5, the cable moves finger 4 away fromfinger 3 (abduction). A similar cable can move finger 3 away from finger4 (abduction).

Still referring to FIG. 1, the thumb 2 can pivot around an axis throughpivotal connector 20 or similar pivot arrangement, by means of a cable(not visible), and a pullback-spring 19. Pivotal connector 20 can be ascrew 21, or other suitable structure. Pivotal connector 20 allows thethumb 2 to move transversely. As a result, the thumb 2 can move tooppose a selected finger, so as to grip between the thumb and theselected individual finger. Thumb 2 can also move with respect to thefingers in a direction determined by the positioning of the proximal andmiddle phalanx joints. This provides for control of the force of thegrip between the thumb and a finger. Accordingly, the robot hand withthe thumb and fingers can mimic the movements of a hand with anopposable thumb, e.g. a human hand.

Referring to FIGS. 4A and 4B, a second embodiment of a robot hand 1 isshown. FIG. 4A is a top view of robot hand 1. FIG. 4B is a side view ofrobot hand 1. The robot hand 1 comprises a hand piece 21 with a thumb22, a first finger 23, and a second finger 24. According to thisembodiment, the robot hand 1 can rotate via cables using a pulleymechanism around a pivot point 25 but may not be able to spread (abduct)fingers 23 and 24. In FIGS. 4A and 4B, the robot hand 1 includes a wristregion 61. The thumb 22 has two phalanxes 26 and 27 which are connectedat joint 60. The joint 60, between phalanxes 26 and 27, can be similarto joints 115, 115′, 115″, 116, 116′ or 116″ as described for FIG. 1. InFIG. 4A, phalanx 26 is extended relative to hand piece 21 and phalanx 27is flexed relative to phalanx 26.

It will be appreciated that when the fingers/thumb are generally intheir straight positions, the robot hand 1 with a shaft 28 attached tothe hand can pass through a medical guide such as a trocar. That is, inone embodiment, the robot hand device is of an appropriate size to passthrough a small incision for use in a minimally invasive procedure suchas a laparoscopic procedure.

Referring again to FIGS. 3A and 3B, the operation of finger 3 isdemonstrated. It will be appreciated that the discussion related tooperation and function of finger 3 is applicable to thumb 2, finger 4and any additional fingers which may be used. The cables 12′ and 13′ canbe pulled either by a remote controller or a local controller. Asdiscussed above, the cable 13′ is shown to be located in the finger topass on the volar aspect 151 ′ of the proximal axis 112′ throughproximal phalanx joint 116′ between the base phalanx 7′ and the middlephalanx 8′, pass into the dorsal aspect 150′ of middle phalanx 8′ downto the volar aspect 151 ′ of the middle phalanx 8′ through the spring17′, and is connected to the end phalanx 9′ in the hole 15′ at 14′. Ifthe cable 13′ is pulled, the cable 13′ rotates the end phalanx 9′relative to the middle phalanx 8′. If the cable 13′ is loosened, thespring 17′ biases against the end phalanx 9′ which will tend tostraighten the finger between the end phalanx 9′ and the middle phalanx8′. The cable 13′ does not move the proximal phalanx joint 116′, becausethe cable 13′ does not have a spring around it and will cross the joint116′ near the pivot point of proximal axis 112′. FIG. 3B shows thefinger 3 in a straight position where the spring 17′ straightens thefinger.

FIG. 5 shows that the shaft 28 can be disconnected from a flexibletransfer unit 47 by a disconnecting unit 30 so that an exemplary robothand 29 can be disconnected from the system to be sterilized or disposedand/or changed with a new hand. The cables are retained inside aflexible transfer unit 47 and connected to a motor unit 48. Operationalmotors of motor unit 48 can be controlled by a computer 49.

FIG. 6 shows a cross-section of flexible transfer unit 47 including apulley or cable 54 having a core assembly 51 and a sheath 50. FIG. 7shows the cross-section of another type of flexible transfer unit 47including a pulley or cable 54 with a core assembly 51, a sheath 50, anda filling 52.

FIG. 8 illustrates a schematic view of a circuit of a control system foroperating a robot hand. In one embodiment, all control functions areoperated and controlled by a micro controller system 42. The robot handcan be controlled by a digital input device 39 or an analog input device38. The analog input device 38 presets nominal values for the movementof the robot hand.

Program and data for a controller 43 are saved in a working memory. AnA/D converter 44 together with an analog multiplexer 40 is used foracquisition of measured values for positioning a robot hand. The serialinterfaces RS232 (45) are used to control the robot hand from a mastersystem and to connect the digital input device 39.

The controller 43 produces directional signals which are transmitted bya port multiplexer 41 to a motor controller 31 to control motors 35. Themotor controller 31 generates special signals for the motors 35 withinterfaces 32 and powers the signals with drivers 34. The motors 35 canbe linear motors or rotary motors. It will be appreciated that othertypes of suitable motors can be used.

In one embodiment, the analog multiplexer 40 transmits the signal ofposition sensors 36 in the robot hand to a channel of the A/D converter44. A power supply 30 delivers power with a suitable voltage for themotors 35 and for the micro-controller system 42 and port extensions.

One method of operating a robot hand is as follows:

balancing particular channels (e.g. balance of initial and end values)by manual or other means;

calibrating the robot hand automatically;

adjusting all axes to an analog nominal value;

adjusting all axes to an analog nominal value and memorizing values;

reproducing memorized values in form of movements; and

adjusting all axes to a digital nominal value.

It will be appreciated that the thumbs 2, 22 and fingers 3, 4, 23, 24and other parts of the robot hand are exemplary and can be varied insize, shape, and relative position without departing from the principlesof the present invention. It will also be appreciated that the locationsand extending directions of the pulleys (or cables), springs, joints,notches, pivotal connections, etc., can be varied according to theprinciples of the present invention.

In addition, the thumb and fingers of the robot hand can be made ofmetal, such as stainless steel, or plastic or a combination of plasticand metal. The pulleys (or cables) can be made out of steel wires. Itwill be appreciated that other suitable materials can be used withoutdeparting from the principles of the invention.

Further, in one embodiment, the robot hand is made in a dimension whichallows the hand to pass through a 10 mm diameter trocar. It will beappreciated that other dimensions can be used according to theprinciples of the invention. One of the advantages of having a smallerdimension is that it allows a smaller “human” hand, i.e. a robot hand,to mimic movements of a real human hand in limited space environments.

A device of the invention can be operated using mechanical inputinformation from a human hand or electrical input information from acomputer or from a human hand through a glove worn by an operator fordetecting finger positions by the operator and operatively connectingthe detected position to the device.

As one skilled in the art appreciates that various modifications may bemade to the above described embodiment without departing from the spiritand scope of the invention, the invention thus resides in the claimshereafter appended.

What is claimed is:
 1. A robot hand comprising: a thumb including: athumb base phalanx; a thumb middle phalanx; a thumb distal phalanx; afirst pivotal thumb joint between the thumb distal phalanx and the thumbmiddle phalanx; a second pivotal thumb joint between the thumb middlephalanx and the thumb base phalanx; a first thumb cable passing throughthe thumb base phalanx and the thumb middle phalanx and attaching to thethumb distal phalanx, and a second thumb cable passing through the thumbbase phalanx and attaching to the thumb middle phalanx, the thumb beingtransversely movable with respect to movement of the thumb phalanxesabout the first and second thumb joints; and at least two fingersdisposed on an opposite side of the thumb, each of the fingersincluding: a finger base phalanx; a finger middle phalanx; a fingerdistal phalanx; a first pivotal finger joint between the finger distalphalanx and the finger middle phalanx; a second pivotal finger jointbetween the finger middle phalanx and the finger base phalanx; a firstfinger cable passing through the finger base phalanx and the fingermiddle phalanx and attaching to the finger distal phalanx and a secondfinger cable passing through the finger base phalanx and attaching tothe finger middle phalanx; and at least one spiral spring disposed at atleast one of the pivotal thumb and finger joints to spring-bias the atleast one of the thumb and finger joints in a straight position; whereinone of the at least one of the pivotal thumb and finger joints is bentupon exertion of a force on a cable associated with the one of the atleast one of the pivotal thumb and finger joints.
 2. A robot handaccording to claim 1, wherein at least one of the cables is moved by acontroller.
 3. A robot hand according to claim 2, further comprising aflange, the robot hand being disconnectable by the flange from acontrolling system.
 4. A robot hand according to claim 1, wherein one ofthe first thumb cable and the first finger cables passes through the atleast one spiral spring.
 5. A robot hand according to claim 1, furthercomprising a disposable glove which houses the thumb and the at leasttwo fingers.
 6. A robot hand according to claim 1, wherein when thethumb and at leat two fingers are in a substantially linear position,the hand can be passed through a medical trocar.
 7. A robot handaccording to claim 1, wherein the at least two fingers can abduct andadduct relative to each other.
 8. A robot hand according to claim 1wherein the thumb is moveable such as to oppose a selected one of the atleast tow fingers and grip between the selected one of at least twofingers.
 9. A robot hand according to claim 1 wherein the first thumbcable attaches to a proximal end of the distal thumb phalanx.
 10. Arobot hand according to claim 1 wherein the first thumb cable passesthrough the thumb base phalanx on a volar aspect of a pivot axis at thesecond thumb joint.
 11. A robot hand according to claim 1, wherein thesecond pivotal finger joint defines a first axis of rotation at a pivot,the finger base phalanx defines a finger base phalanx longitudinal axisbetween a distal end of the finger base phalanx and a proximal end ofthe finger base phalanx, and the at least one spring includes a firstspring disposed relative to the pivot in a direction substantiallyperpendicular to both the finger base phalanx longitudinal axis and thefirst rotation axis.
 12. A robot hand according to claim 11, wherein thefirst spring is a coil spring and has a longitudinal spring axissubstantially parallel to the finger base phalanx longitudinal axis whenthe first spring is in a relaxed position, and the second finger cablepasses through the coil spring.
 13. A robot hand according to claim 11,wherein the first finger cable passes between the first spring and thepivot to the finger middle phalanx, closer to the pivot than to thefirst spring.
 14. A robot hand according to claim 1, further comprisinga hand base, the thumb base phalanx and the finger base phalanx eachbeing attached to the hand base, wherein, when the thumb and the atleast two fingers are in a relaxed position without significant tensionon the thumb cables and the finger cables, the at least two fingers andthumb lie substantially parallel to one another, pointing in a distaldirection from the hand base to pass through a trocar.
 15. A robot handcomprising: a hand base; at least two fingers, each of the fingersincluding: a first finger phalanx attached to the hand base and a secondfinger phalanx; a first pivotal finger joint connecting the first fingerphalanx and the second finger phalanx; a first finger cable passingthrough the first finger phalanx and attaching to the second fingerphalanx; and a finger joint spring disposed between the first and secondfinger phalanges, at the first pivotal finger joint, to spring-bias thefirst finger joint so that the second finger phalanx is substantiallyparallel to the first finger phalanx, wherein the first finger joint isbent upon exertion of a force on the first finger cable; and a thumbopposing the first two fingers, the thumb including: a first thumbphalanx attached to the hand base and a second thumb phalanx; a firstpivotal thumb joint connecting the first thumb phalanx and the secondthumb phalanx; a first thumb cable passing through the first thumbphalanx and attaching to the second thumb phalanx; a spring disposedbetween the first and second thumb phalanges, at the first pivotal thumbjoint, to spring-bias the first thumb joint so that the second thumbphalanx is substantially parallel to the first thumb phalanx, whereinthe first pivotal thumb joint is bent upon exertion of a force on thefirst thumb cable, and a third phalanx pivotally attached to one of thesecond thumb phalanx and the second finger phalanges, a second cablepassing through the one of the second thumb phalanx and second fingerphalanges and attaching to the third phalanx, a third phalanx springbeing positioned between the third phalanx and the one of the secondthumb phalanx and second finger phalanges to spring-bias the thirdphalanx to be substantially parallel to the one of the second thumbphalanx and second finger phalanges when there is no spring-bendingtension on the second cable.
 16. A robot hand as recited in claim 15wherein, in at least one of the fingers, the first finger pivotal jointdefines a first axis of rotation and the first finger phalanx ispivotally attached to the hand base to pivot about an axis substantiallyperpendicular to the first axis of rotation.
 17. A robot hand as recitedin claim 15, wherein, in at least one of the fingers, the first pivotalfinger joint defines a first axis of rotation at a pivot and the firstfinger phalanx defines first finger phalanx longitudinal axis between adistal end of the first finger phalanx and a proximal end of the firstfinger phalanx, and the spring is disposed relative to the pivot in adirection substantially perpendicular to both the first axis of rotationand the first finger phalanx longitudinal axis.
 18. A robot handaccording to claim 17, wherein the spring is a coil spring and has alongitudinal spring axis substantially parallel to the first fingerphalanx longitudinal axis when the coil spring is in a relaxed position,and the first finger cable passes through the coil spring between thefirst and second finger phalanges.
 19. A robot hand comprising: a thumbincluding: a thumb base phalanx; a thumb middle phalanx; a thumb distalphalanx; a first pivotal thumb joint between the thumb distal phalanxand the thumb middle phalanx; a second pivotal thumb joint between thethumb middle phalanx and the thumb base phalanx; a first thumb cablepassing through the thumb base phalanx and the thumb middle phalanx andattaching to the thumb distal phalanx, and a second thumb cable passingthrough the thumb base phalanx and attaching to the thumb middlephalanx, the thumb being transversely movable with respect to movementof the thumb phalanxes about the first and second thumb joints; and atleast two fingers disposed on an opposite side of the thumb, each of thefingers including: a finger base phalanx; a finger middle phalanx; afinger distal phalanx; a first pivotal finger joint between the fingerdistal phalanx and the finger middle phalanx; a second pivotal fingerjoint between the finger middle phalanx and the finger base phalanx; afirst finger cable passing through the finger base phalanx and thefinger middle phalanx and attaching to the finger distal phalanx and asecond finger cable passing through the finger base phalanx andattaching to the finger middle phalanx; and at least one spring disposedat at least one of the pivotal thumb and finger joints to spring-biasthe at least one of the thumb and finger joints in a straight position,wherein one of the at least one of the pivotal thumb and finger jointsis bent upon exertion of a force on a cable associated with the one ofthe at least one of the pivotal thumb and finger joints, and the secondpivotal finger joint defines a first axis of rotation at a pivot, thefinger base phalanx defines a finger base phalanx longitudinal axisbetween a distal end of the finger base phalanx and a proximal end ofthe finger base phalanx, and the at least one spring includes a firstspring disposed relative to the pivot in a direction substantiallyperpendicular to both the finger base phalanx longitudinal axis and thefirst rotation axis.
 20. A robot hand according to claim 19, wherein atleast one of the cables is moved by a controller.
 21. A robot handaccording to claim 20, further comprising a flange, the robot hand beingdisconnectable by the flange from a controlling system.
 22. A robot handaccording to claim 19, wherein one of the first thumb cable and thefirst finger cables passes through the at least one spring.
 23. A robothand according to claim 19, further comprising a disposable glovehousing the thumb and the at least two fingers.
 24. A robot handaccording to claim 19, wherein the at least two fingers can abduct andadduct relative to each other.
 25. A robot hand according to claim 19,wherein the first spring is a coil spring and has a longitudinal springaxis substantially parallel to the finger base phalanx longitudinal axiswhen the first spring is in a relaxed position, and the second fingercable passes through the coil spring.
 26. A robot hand according toclaim 19, wherein the first finger cable passes between the first springand the pivot to the finger middle phalanx, closer to the pivot than tothe first spring.
 27. A robot hand according to claim 19, furthercomprising a hand base, the thumb base phalanx and the finger basephalanx each being attached to the hand base, wherein, when the thumband the at least two fingers are in a relaxed position withoutsignificant tension on the thumb cables and the finger cables, the atleast two fingers and thumb lie substantially parallel to one another,pointing in a distal direction from the hand base to pass through atrocar.
 28. A robot hand comprising: a thumb including: a thumb basephalanx; a thumb middle phalanx; a thumb distal phalanx; a first pivotalthumb joint between the thumb distal phalanx and the thumb middlephalanx; a second pivotal thumb joint between the thumb middle phalanxand the thumb base phalanx; a first thumb cable passing through thethumb base phalanx and the thumb middle phalanx and attaching to thethumb distal phalanx, and a second thumb cable passing through the thumbbase phalanx and attaching to the thumb middle phalanx, the thumb beingtransversely movable with respect to movement of the thumb phalanxesabout the first and second thumb joints; and at least two fingersdisposed on an opposite side of the thumb, each of the fingersincluding: a finger base phalanx; a finger middle phalanx; a fingerdistal phalanx; a first pivotal finger joint between the finger distalphalanx and the finger middle phalanx; a second pivotal finger jointbetween the finger middle phalanx and the finger base phalanx; a firstfinger cable passing through the finger base phalanx and the fingermiddle phalanx and attaching to the finger distal phalanx and a secondfinger cable passing through the finger base phalanx and attaching tothe finger middle phalanx; and a first spring disposed at one of thepivotal thumb and finger joints to spring-bias the one of the thumb andfinger joints in a straight position, wherein the one of the pivotalthumb and finger joints is bent upon exertion of a force on a cableassociated with the one of the at least one of the pivotal thumb andfinger joints, and the cable associated with the one of the pivotalthumb and finger joints passes between the first spring and a pivot ofthe one of the pivotal thumb and finger joints, closer to the pivot thanto the first spring.
 29. A robot hand according to claim 28, wherein atleast one of the cables is moved by a controller.
 30. A robot handaccording to claim 28, further comprising a flange, the robot hand beingdisconnectable by the flange from a controlling system.
 31. A robot handaccording to claim 28, wherein one of the first thumb cable and thefirst finger cables passes through the first spring.
 32. A robot handaccording to claim 28, further comprising a disposable glove housing thethumb and the at least two fingers.
 33. A robot hand according to claim28, wherein the at least two fingers can abduct and adduct relative toeach other.
 34. A robot hand according to claim 28, wherein the secondpivotal finger joint defines a first axis of rotation at a pivot, thefinger base phalanx defines a finger base phalanx longitudinal axisbetween a distal end of the finger base phalanx and a proximal end ofthe finger base phalanx, and the first spring is disposed relative tothe pivot in a direction substantially perpendicular to both the fingerbase phalanx longitudinal axis and the first rotation axis.
 35. A robothand according to claim 34, wherein the first spring is a coil springand has a longitudinal spring axis substantially parallel to the fingerbase phalanx longitudinal axis when the first spring is in a relaxedposition, and the second finger cable passes through the coil spring.36. A robot hand according to claim 28, further comprising a hand base,the thumb base phalanx and the finger base phalanx each being attachedto the hand base, wherein, when the thumb and the at least two fingersare in a relaxed position without significant tension on the thumbcables and the finger cables, the at least two fingers and thumb liesubstantially parallel to one another, pointing in a distal directionfrom the hand base to pass through a trocar.
 37. A robot handcomprising: a hand base; at least two fingers, each of the fingersincluding: a first finger phalanx attached to the hand base and a secondfinger phalanx; a first pivotal finger joint connecting the first fingerphalanx and the second finger phalanx; a first finger cable passingthrough the first finger phalanx and attaching to the second fingerphalanx; and a finger joint spring disposed between the first and secondfinger phalanges, at the first pivotal finger joint, to spring-bias thefirst finger joint so that the second finger phalanx is substantiallyparallel to the first finger phalanx, the first being bent upon exertionof a force on the first finger cable; and a thumb opposing the first twofingers, the thumb including: a first thumb phalanx attached to the handbase and a second thumb phalanx; a first pivotal thumb joint connectingthe first thumb phalanx and the second thumb phalanx; a first thumbcable passing through the first thumb phalanx and attaching to thesecond thumb phalanx; a spring disposed between the first and secondthumb phalanges, at the first pivotal thumb joint, to spring-bias thefirst thumb joint so that the second thumb phalanx is substantiallyparallel to the first thumb phalanx, the first pivotal thumb joint beingbent upon exertion of a force on the first thumb cable wherein, in atleast one of the fingers, the first pivotal finger joint defines a firstaxis of rotation at a pivot and the first finger phalanx defines firstfinger phalanx longitudinal axis between a distal end of the firstfinger phalanx and a proximal end of the first finger phalanx, and thespring is disposed relative to the pivot in a direction substantiallyperpendicular to both the first axis of rotation and the first fingerphalanx longitudinal axis.
 38. A robot hand as recited in claim 37,wherein, in at least one of the fingers, the first finger pivotal jointdefines a first axis of rotation and the first finger phalanx ispivotally attached to the hand base to pivot about an axis substantiallyperpendicular to the first axis of rotation.
 39. A robot hand as recitedin claim 37, wherein the spring is a coil spring and has a longitudinalspring axis substantially parallel to the first finger phalanxlongitudinal axis when the coil spring is in a relaxed position, and thefirst finger cable passes through the coil spring between the first andsecond finger phalanges.
 40. A robot hand as recited in claim 37,further comprising a third phalanx pivotally attached to one of thesecond thumb phalanx and the second finger phalanges, a second cablepassing through the one of the second thumb phalanx and second fingerphalanges and attaching to the third phalanx, a third phalanx springbeing positioned between the third phalanx and the one of the secondthumb phalanx and second finger phalanges to spring-bias the thirdphalanx to be substantially parallel to the one of the second thumbphalanx and second finger phalanges when there is no significant tensionon the second cable.